phosphor-scroll-engine

Implements IPlacementEngine for screens running Scrolling mode. Windows form columns on an endless strip and the screen is a viewport onto it, so opening a window slides its neighbours aside and scrolls the view instead of resizing them. The engine owns column widths and their preset cycles, whether a column stacks its windows or tabs them, consume-and-expel between columns, focus centering policies, and the stash a minimized window returns from. StripAxis abstracts the direction, so the same code runs a side-to-side strip on a landscape monitor and a top-to-bottom one on a portrait panel without a second implementation. Windows too large for the strip fall back to the shared floating support.